Pneumatic railway



( N o M o d e 1 3 S h e e t s S h e e t 1.

M. BODEFELD. AAAAAAAAAAAAA WAY.

No 408,729. Patented May 21 1889.

(No Model.) 3 Sheets-Sheet 2.,

'M. BODEFELD.

PNEUMATIC RAILWAY. No. 403,729. Patented May 21 1889.

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3 Sheets-Sheet 3..

(No Model.)

M. BODEFELD.

PNEUMATIC RAILWAY.

Patented May 21 1889.

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Av w 0 a m m 6 N attoz-nc NITED STATES PATENT OFFIC MEINOLPH BODEFELD,OF ST. LOUIS, MISSOURI.

PNEUMATIC RAILWAY.

SPECIFICATION forming part of Letters Patent No. 403,729, dated May 21,1889.

Application filed November 23, 1887. Serial No. 255,985. (No model.)

To all whom it may concern:

Be it known that I, MEINOLPH BonEFELD, of St. Louis, in the State ofMissouri, have invented certain new and useful Improvements in PneumaticRailways; and I do hereby declare the following to be a full, clear, andeX- act description of the invention, such as will enable others skilledin the art to which it appertains to make and use the same.

My invention relates to an improvement in pneumatic railways.

Prior to my invention in the construction of pneumatic railways the carhas been provided with a depending portion to enter a tube and has beenthere connected with a piston. \Vith such arrangements a flap wasnecessary to cover the opening in the tube and prevent the escape of thecompressed air contained therein for propelling the piston, or toprevent the admission of air when exhaust-air devices were employed, andto retain this flap to its seat various devices have been employed whichhave rendered the system of such railways unnecessarily complicated andexpensive, owing to the large number of parts used.

It is the object of my present invention to simplify and cheapen theconstruction of pneumatic railways, and at the same time render the sameeffective in operation.

A further object is to provide a tube from which the airis exhaustedwith a flap of elastic material to cover a longitudinal opening in thetube, and that will be held firmly to its seat by suction produced by apartial vacuum in the tube.

A further object is to so construct the bracket attached to the car andwhich passes through the opening in the tube that it shall raise theabove-mentioned flap to permit its passage, and in such a manner thatlittle or no air will find its way into the tube.

A further object is to furnish the hollow piston which passes throughthe tube with mechanism whereby both ends may be simultaneously openedwhen it is desired to stop the car.

lVith these objects in view my invention consists in the novelconstruction and peculiar combination and arrangement of parts, as willbe hereinafter set forth, and pointed out in the claims.

In the accompanying drawings, Figure 1 is a longitudinal sectional Viewof a conduit embodying my invention. Fig. 2 is a cross-section of thesame. Fig. 3 is a view illustrating the arrangement of conduits at acrossing. Fig. 4. is a longitudinal sectional view of a modification.Fig. 5 is a cross-section of the same.

A indicates a conduit similar in construction to those commonly used forcable railways, but preferably somewhat larger, for the reception of atube, B. This tube B is made of iron or other suitable material andsupported in the conduit A by means of rods or braces a, thus leaving aspace beneath the tube B for the reception of drainage, which may becarried oft through suitable drainpipes to asewer or other place.

The tube 13 is provided at its top and throughout its length with anopening, 1), and is flattened slightly on each side of said openin forthe reception of-a sealing-strip, O, as shown. This sealing-strip ispreferably made of indiarubber or other elastic material, and secured byone edge to the flattened portion of the tube, so as to cover theopeningb and beheld firmly thereon by pressure of air brought to bearupon it, there being a partial vacuum produced in the tube by anysuitable means. The space between the top of the tube B and the top ofthe conduit A will preferably be suiiicient to admit a man, so thatrepairs may be made when required. Tracks are laid in the usual mannerparallel with the conduit A at each side, upon which a car is adapted tol'llll.

Each car is provided at its bottom with a depcndin g bracket, D, the armD of which is secured at its upper end to a frame,l) ,which latter isattached to the truck of the car by means of bolts D, strong springs Ebeing made to encircle these bolts and bear upon a nut screwed upontheir lower ends. By this construction jolting of the car in passingover an obstruction is compensated for.

Secured to the lower end of the arm D is a laterally-extending arm, G,and fixed to the free end of this arm is a do\vnwardly-extending arm, G.The arm G is secured to a plate, H, which extends therefrom in adirection parallel with the arm G, and is adapted to slide upon the topof the tube 1). As shown in Fig. 2, this bracket, with the exception of.operate it.

the arm D, is inclosed within the conduit A, said arm D extendingthrough the opening a of the conduit and connected to the truck of thecar, as above explained. The plate H is beveled on its upper face fromthe center to each end to enter beneath the flap O, for a purpose whichwill be hereinafter described.

To the under side of the plate His secured a web or flange, I, adaptedto slide in the opening I) of the tube and project somewhat beyond theends of the plate H, as shown in Fig. 1. The bracket D and web I maybemade in a single piece, if desired.

A piston, M, of cast-steel or other suitable material, and preferablyabout the same length as the plate H, is firmly secured to the bottomedge of the web I, or, if desired, may be made integral with said web.The piston M is provided around its periphery with two or more groovesfor the reception of packin gstrips d, which are placed in thesegrooves, so that they shall be capable of a slightexpansion outwardly,and thus cause the piston to fit snugly within the tube A.

In order to insure such expansion of the packing strips or rings, eachis made of two or more pieces of suitable material, which have theirends overlapped. Behind these packing-rings and fitted in sockets madein the base of the grooves are a series of spiral springs,'j, furnishedat their outer extremities with small plates or washers 70, which bearagainst the under faces of the packingrings 2', and thus these rings arenormally forced outwardly against the inner surface of the tube 13. Thepacking-rings should be furnished with rabbets on one face to enterbeneath a plate secured to the piston, and

thus prevent said packing-rings from moving too far when the piston isout of the tube.

The piston M is made with a passage, which extends from end to endthereof, as shown in Figs. 1 and 5. Pivoted at each end I of thispassage is a disk-valve, e, which disksare furnished on theirperipheries with suit able packing material to Mounted upon the car,preferably the front platform, is a rod, N, provided at its upper endwith a crank arm or wheel by which to The rod N extends downwardlythrough the bottom of the platform of the car into the conduit A, beingset into a recess made in the arm D. This rod is then bent outwardlysome distance beyond the bracket D, then downwardly, and then inwardly,thus producing a crank-arm, O. The lower inwardly-extendin g arm, 0, ofthis crank-arm is adapted to enter an elongated or V-shaped slot orrecess, m, made in one edge of plate H, in which slot said arm has asliding movement, the lower portion of the arm G being sufficiently cutaway to permit the entrance of arm 0 into the slot or recess m. The arm0 is connected at its free inner end within the slot m to a verticalrod, P, pivoted at its produce air-tight joints when the valves areclosed.

upper end in the plate H and at its lower end in the bottom of thepiston M.

Fixed to the rod P within the piston M is a short cross-bar, Q,extending an equal distance on each side of said rod and provided at ornear its ends with perforations for the reception of one end of rods RR. The opposite ends of these rods are extended outwardly toward theends of the piston and connected to an eye or loop fixed to the upper orlower portions of the disk-valves e, as shown in Fig. 2. By thisconstruction it will be seen than when the rod N is turned one way itwill operate to open the valves 6 and when turned in the oppositedirection will operate to close them.

The apparatus being constructed as above set forth, the air is exhaustedfrom the tube B by means of a suitable engine at a central station. Theair in the tube being thus exhausted and the valves 6 of the pistonclosed air-tight, the piston will move through the tube l3, and thus thecar attached to it is moved upon its tracks. WVhile the car is moving,the projecting end of the web or flange I will serve to lift the flap Oslightly, said flap being further lifted by the plate H, which movesbeneath it. This plate being beveled from the center toward each end,the raising of the flap will be gradual, and after the car has passedwill close down behind it by means of suction.

From this construction it will be seen that there is always a tendencyof the flap O to retain its seat over the opening in the tube 13, andthat the raising and lowering of it by the plate II will cause little orno air to be admitted into the tube, and if outside air should find itsway into the tube it is immediately exhausted by the engine at thecentral station. When it is desired to stop a car, it is simplynecessary to operate the rod N, as above explained, to open thedisk-valves e and permit the circuit to pass through the piston, andtherefore exert no pulling force thereto. If the car is to be stoppedimmediately, its momentum may be arrested by the ordinary brakes appliedto the car-wheels. YVhen it is desired to use compressed air to propelthe piston M in climbing heavy grades, the arrangement of apparatusillustrated in Figs. 4 and 5 will preferably be used.

If the flap 0 were used as shown in Fig. 2, the compressed air wouldtend to force the same away from its seat, and to retain said flap inposition and render the tube air-tight two strips or plates, S S, toproject over the flap and limit its upward movement, are preferablysecured to the flattened top of the tube B, as shown in Fig. 5 With thisarrangement the web I and plate H will be dispensedwith and the arm G'secured directly to the piston, the opening I) in the tube B being ofsufficient width to receive the flap O and arm G. The arm G thereforeoccupies the same position in this form of the invention as the web I inthe previously-described arrangement, and, in fact, takes the place ofsaid web I and serves to connect the piston with the bracket whichprotrudes from the car. The under face of arm G of bracket D will be soarranged relatively to the piston that the flap 0 shall pass betweenthem without permitting escape of air. The under face of the arm G isbeveled from the center toward each -end to enter between the plates S Sand the flap to force it down to permit the passage of the bracket D. Inorder to prevent a current of air passing around the piston M throughthe opening 1), said opening will be closed by projections z, fixed toor made integral with the piston M and adapted to bear against or form abearing for the under face of the flap G.

hen the above-described arrangement of bracket is used, the crank-arm ofthe rod N will be made to work in a recess made in the back of the armG. A flap, X, of rubber or other suitable material, is secured to theplate S and adapted to extend over the opening I) of the tube 13 toexclude dirt, the. This strip is raised by the beveled end of the armDin its passage through the opening I), as shown in Figs. 4: and 5.lVhere two tubes or conduits cross, the arrangement shown in Fig. 3 willbe adopted. The two tubes will be made to communicate in a mannersimilarto the joining of two gas or water pipes, and the tubes will befurnished at each side of the point of crossing with valves 0 o p 1').These valves remain normally closed, so that the currents in therespective tubes will not conflict with each other. The current will bemade continuous past these valves by means of bypasses q and 0', theseby-passes communicatin g with the tubes at points beyond the valves.Yhen a car is passing a crossing in the direction indicated by thearrows, the valve 0 is so arranged that when the piston M strikes it, it

will be opened down in a suitable recess, 0 made in the tube to receiveit, and the piston M is then allowed to pass; but when the pistonreaches the valve 0' this valve, which is preferably adapted to slide,will have to be operated manually.

It is preferable that the piston be provided with a curved rod, 0 ateach end, said rod being so arranged as not to conflict with the valves2, and furnished with a knob, 0, to strike the valves in the tubes toopen them. The valves p1) of the cross-tube will of course beconstructed and operated in the same manner as the valves 0 0.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is

1. In a pneumatic railway system, the com bination, with two pneumatictubes which cross, of by-passes communicating with the tubes to bridgethe point of crossing, an auto matieally-operated valve in each tube atone side of the point of crossing, and amanuallyoperated valve at theopposite side of the point of crossing, substantially as set forth.

2. In a pneumatic system, the combination, with a tube having alongitudinal opening, of an elastic flap to close said opening, a Webadapted to slide in the opening, a bevel-plate secured to the top of theweb to move the flap, a bracket connecting the bevel-plate, and a frameattached to the car-truck, and a piston secured to the bottom of saidweb and adapted to slide in the tube, substantially as set forth.

In testimony whereof I have signed this specification in the presence oftwo subscribing witnesses.

MEINOLPH BODEFELD.

Vitnesses:

R. S. FERGUSON, S. G. NOTTINGHAM.

